One of the goals when developing contemporary machine tools and machining centers is to allow for as many different machining processes as possible in one setting on a workpiece. The means to achieve this most often is through the use of a magazine with preprogrammed exchangeable units, which feed the work spindle with various tools and/or the work bench with paletted workpieces according to the preprogrammed process. Some types of finishing, such as the fine machining of the surfaces of workpieces (planishing, scraping, polishing) are not easily integrated into program controlled machining processes of finishing workpieces. This is particularly true because fine and finest machining of surfaces of workpieces take a long time during which the machine tool cannot be used for other machining processes.
For this reason special machines have had to be used for fine machining of workpiece surfaces and similar finishing processes. However, there are extended quiet periods in every plant during which the entire machine center is used only partly or not at all, as for example during night shifts, on weekends and holidays